Electromagnet



J. W. BISHOP ifiLECTROMAGNET June 22 1926. 1,589,506

Filed Feb. 12. 1923 Patented June 22, 1926.

UNITED STATES PATENT OFFICE.

JOSEPH WQBISHOP, OF MUSKEGON, MICHIGAN, ASSIGNOR TO THE BRUNSWICK BALKE-COLLENDER 00., OF WILMINGTON, DELAWARE, A CORPORATION OF DEL- AWARE.

ELECTROMAGNET.

Application filed February 12, 1923.

This invention relates to electromagnets of the type disclosed in United States Letters Patent No. 1,190,647 patented July 11, 1916 and particularly adapted for use in connection with automatic pin setting ma chines for bowling alleys.

The object of the invention is to provide an electromagnet light in weight having the lines of force equally distributed over a face of relatively large superficial area so that the lifting power of the magnet at any point on. its face is equal to the lifting power of the magnet at every other point on its face.

In the accompanying drawings illustrating a selected embodiment of the invention Fig. 1 is a verticalsectional View;

Fig. 2 is a top plan view of the core.

Referring to the drawings, 5 indicates a core, preferably made of soft iron, which is flared at 6 and has a peripheral flange 7 to provide a face 8 of relatively large superficial area compared to the diameter of the core 5. This face is integral with the flared part 6 of the core 5 and is preferably circular in shape. Theflared part 6 is provided with air passages 9 formed by transverse intersecting bores extending entirely therethrough. A winding consisting of a plurality of turns of insulated conducting material 10 are disposed about the core in the usual manner between the face plate 8 and the back plate 11 and are adapted to be connected to a source of electric current which energizes the electromagnet. A bolt 12 is threadedly engaged with the core to hold the parts together and to secure the electromagnet to the supporting structure (not shown).

My invention provides an electromagnet of simple construction, with a face of sufficient superficial area for the purpose to which the magnet is adapted, and with the lines of force equally distributed throughout the entire face. While the electromagnet may be used for many different purposes it will be found particularly useful in automatic pin setting machines for bowling alleys to lift a pin from the alley bed as may be required and from any position, within the range of the electromagnet, without causing the pin totilt so that by lowering the magnet the pin can be replaced upon the Serial No. 618,459.

alley bed in the exact position from which it was lifted. In the game of bowling it frequently happens that some of the ins knocked down by a ball remain as cad Wood upon the alley bed and electromagnets have been employed for lifting the standing pins from the alley bed so that the fallen pins can be swept into the pit, after which the lifted pins are replaced upon the alley bed. Some times these standing pins are displaced from their normal position upon the pin spots on the alley bed by the blow of the ball or by the pins which. are knocked down and it is necessary under the present rules and regulations of the game to replace these standing pins in the exact positions to which they have been removed, and it is necessary to provide the lifting magnet for each pin with a face plate having a superficial area of relatively large size to include a considerable displacement of the pin from its spot so that the magnet may lift the pin and replace it as desired. It is important, therefore, that the lines of force should be equally distributed over the lifting face of the magnet to accomplish this result, for otherwise the tendency would be to pull or tilt the pin to one side so that, when it is lifted free from the alley bed, the pin would swing out of its proper position and be replaced upon the alley bed in a position different from that from which it was lifted. This would be a departure from the standard rules and regulations of the game and be unfair to players. By providing the passages through the core I overcome the flux density on the center of the plate and prevent the magnet drawing the pin out of line before coming in contact therewith. Furthermore, since ten of these electromagnets are used on the movable supporting frame of an automatic pin setter it is highly desirable to keep the weight as low as possible and I have accomplished this by making the electromagnet much lighter than other magnets which have been used heretofore.

I have illustrated the electromagnet in a size, shape and form which I consider particularly desirable for its use in automatic pin setting machines, but I reserve the right to make all such changes in the form, construction and arrangement of parts, as well 2. An electroinagnet comprising a core 10 having a substantially flat face of relatively large snperfieial area, a '\Vii1clii1g disposed about said core, said core having a plurality of intersecting passages disposed parallel to said face and extending entirely through 15 said core.

JOSEPH W. iasaor. 

